Table 1.
Demographic and medical correlates of plasma Aβ40 among 997 older adults
| Baseline Characteristics N (%) or Mean (SD) |
Tertile 1 n=333 | Tertile 2 n=331 | Tertile 3 N=333 | p-value |
|---|---|---|---|---|
| Age, years | 73.6 (3.0) | 74.0 (2.8) | 74.5 (2.9) | .0001 |
| Black Race | 201 (60.4) | 190 (57.4) | 147 (44.1) | <.0001 |
| Female Sex | 184 (55.3) | 187 (56.5) | 179 (53.8) | .78 |
| Education (≥HS) | 223 (67.2) | 226 (68.5) | 197 (59.5) | .03 |
| Literacy (REALM, ≥8th grade) | 94 (29.9) | 85 (27.8) | 87 (27.8) | .79 |
| 3MS | 91.0 (5.4) | 91.2 (5.5) | 91.1 (5.2) | 0.90 |
| Social Support* | 171 (51.4) | 165 (49.9) | 152 (45.7) | 0.26 |
| Body Mass Index | 27.7 (5.2) | 28.0 (4.8) | 27.5 (4.8) | .35 |
| Physical Activity (kcal per week) | 1055.5 (2373.2) | 1133.3 (2455.5) | 982.4 (1465.0) | 0.66 |
| Depressive Symptoms (CES-D≤16) | 13 (3.9) | 22 (6.7) | 11 (3.3) | .09 |
| Stroke/TIA History | 25 (7.5) | 33 (10.1) | 37 (11.3) | .25 |
| Diabetes History | 74 (23.2) | 83 (25.6) | 83 (25.9) | .69 |
| Myocardial Infarction History | 25 (7.6) | 38 (11.6) | 42 (12.8) | .07 |
| Cholesterol (mg/dl) | 202.7 (37.6) | 208.4 (41.1) | 202.2 (39.3) | 0.08 |
| Triglycerides (mg/dl) | 126.8 (80.6) | 131.1 (100.5) | 138.5 (68.0) | 0.19 |
| HDL (mg/dl) | 56.6 (17.7) | 55.1 (16.7) | 52.9 (16.5) | 0.02 |
| LDL (mg/dl) | 121.4 (34.5) | 127.2 (35.5) | 121.6 (35.4) | 0.06 |
| APOE e4 allele (≤1 e4 allele) | 96 (30.9) | 101 (32.2) | 93 (29.5) | .77 |
| BDNF (pg/ml) | 23361.6 (10648.3) | 21206.2 (11064.9) | 20944.4 (10022.9) | 0.006 |
| Creatinine (mg/dl) | 1.0 (0.2) | 1.0 (0.3) | 1.2 (0.5) | <.0001 |
| C-reactive Protein (μg/mL) | 3.0 (3.9) | 2.9 (4.0) | 3.4 (7.3) | .42 |
| Tumor Necrosis Factor (pg/ml) | 3.3 (2.1) | 3.2 (1.3) | 3.7 (1.7) | 0.0007 |
| IL-6 (pg/ml) | 2.3 (1.9) | 2.2 (1.7) | 2.4 (1.8) | 0.28 |
| Smoker (Ever vs. Never) | 183 (55.0) | 180 (54.4) | 180 (54.4) | .99 |
*
N (%) below the median; variable defined as a combination of friends, neighbors and relatives who visit per week.
Aβ40 indicates amyloid beta-40; SD standard deviation; HS high school; REALM Rapid Estimate of Adult Literacy in Medicine; 3MS Modified Mini-Mental Status Exam; CES-D Center for Epidemiologic Studies Depression Scale; TIA transient ischemic attack; HDL high-density lipoprotein cholesterol; LDL low-density lipoprotein cholesterol; APOE Apolipoprotein E; BDNF brain-derived neurotrophic factor; IL-6 interleukin-6.